Publications by authors named "Noel W Davies"

Article Synopsis
  • Naudin, a plant species from the Cerrado, shows promise for therapeutic uses, prompting researchers to standardize its aqueous leaf extracts and examine seasonal chemical differences.
  • Seven batches of extracts were analyzed for their total solids, polyphenolic content, flavonoids, and antioxidant activity using techniques like TLC and HPLC.
  • The seasonal study, which spanned from May 2017 to August 2018, found that chemical compositions remain stable throughout the year, indicating that extracts can be consistently produced without major variations in quality.
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Secondary metabolites are suggested as a major mechanism explaining genetic variation in herbivory levels in Pinus radiata. The potential to incorporate these chemical traits into breeding/deployment programmes partly depends on the presence of additive genetic variation for the relevant chemical traits. In this study, near-infrared spectroscopy was used to quantify the constitutive and induced levels of 54 compounds in the bark of trees from 74 P.

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Bark stripping by mammals is a major problem in managed conifer forests worldwide. In Australia, bark stripping in the exotic plantations of Pinus radiata is mainly caused by native marsupials and results in reduced survival, growth, and in extreme cases death of trees. Herbivory is influenced by a balance between primary metabolites that are sources of nutrition and secondary metabolites that act as defences.

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The red fox is a highly adaptable mammal that has established itself world-wide in many different environments. Contributing to its success is a social structure based on chemical signalling between individuals. Urine scent marking behaviour has long been known in foxes, but there has not been a recent study of the chemical composition of fox urine.

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The EAG () family of voltage-gated K channels are important regulators of neuronal and cardiac action potential firing (excitability) and have major roles in human diseases such as epilepsy, schizophrenia, cancer, and sudden cardiac death. A defining feature of EAG (Kv10-12) channels is a highly conserved domain on the N terminus, known as the eag domain, consisting of a Per-ARNT-Sim (PAS) domain capped by a short sequence containing an amphipathic helix (Cap domain). The PAS and Cap domains are both vital for the normal function of EAG channels.

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A major challenge in broader clinical application of Jack Jumper ant venom immunotherapy (JJA VIT) is the scarcity of ant venom which needs to be manually harvested from wild ants. Adjuvants are commonly used for antigen sparing in other vaccines, and thereby could potentially have major benefits to extend JJA supplies if they were to similarly enhance JJA VIT immunogenicity. The purpose of this study was to evaluate the physicochemical and microbiological stability and murine immunogenicity of low-dose JJA VIT formulated with a novel polysaccharide adjuvant referred to as delta inulin or Advax™.

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Like all animals, the red fox uses chemical signals for social communication. The supracaudal or tail gland smells of violets, attributed to the presence of carotenoid degradation products, or apocarotenoids, which commonly occur as aromatics in flowers. We have more fully characterized the scent chemistry of the fox tail gland.

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Psyllids (Hemiptera: Psylloidea) are small sucking insects with high host plant specificity. Despite the primitive olfactory system of psyllids, some species have been suggested to rely on host plant volatiles (HPVs) for seasonal migration between summer deciduous hosts and winter coniferous hosts. Similarly, enhanced attraction of psyllid vectors has been observed as a result of the manipulation of host odors by plant pathogens.

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The originally published version of this article contained an error in the subheading 'Heme is required for CO-dependent channel activation', which was incorrectly given as 'Hame is required for CO-dependent channel activation'. This has now been corrected in both the PDF and HTML versions of the Article.

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Background: The venomous stings of Jack Jumper ant (JJA; species of the Myrmecia pilosula taxonomic group) are a significant public health issue in parts of south-eastern and south-western Australia, causing anaphylaxis in approximately 3% of the population. Three allergenic peptides, Myr p 1, Myr p 2 and Myr p 3, and one histamine-releasing peptide, pilosulin 5, have been fully described, but there are at least 5 additional high molecular weight IgE-binding components that have not been identified.

Objective: To identify IgE-binding components in JJA venom (JJAV) and to relate the IgE recognition of these components to relevant clinical parameters.

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The influence of process parameters on the extraction of anthocyanins from the edible portion of fresh, sweet cherry were investigated. The optimal extraction time and temperature were determined as 90 min and 37 °C, respectively. A solvent/solid ratio of 10 mL/g using 100% acidified solvent resulted in the greatest anthocyanin yield.

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Despite being highly toxic, carbon monoxide (CO) is also an essential intracellular signalling molecule. The mechanisms of CO-dependent cell signalling are poorly defined, but are likely to involve interactions with heme proteins. One such role for CO is in ion channel regulation.

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Strigolactones (SLs) influence the ability of legumes to associate with nitrogen-fixing bacteria. In this study, we determine the precise stage at which SLs influence nodulation. We show that SLs promote infection thread formation, as a null SL-deficient pea () mutant forms significantly fewer infection threads than wild-type plants, and this reduction can be overcome by the application of the synthetic SL GR24.

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Tomato spotted wilt virus (TSWV) causes sporadic but serious disease in Australian potato crops. TSWV is naturally spread to potato by thrips of which Thrips tabaci is the most important. Prior studies indicated possible non-preference of potato cultivars to T.

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Divergence in communication systems should influence the likelihood that individuals from different lineages interbreed, and consequently shape the direction and rate of hybridization. Here, we studied the role of chemical communication in hybridization, and its contribution to asymmetric and sexually selected introgression between two lineages of the common wall lizard (Podarcis muralis). Males of the two lineages differed in the chemical composition of their femoral secretions.

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The tail gland of the red fox (Vulpes vulpes) secretes lipids containing volatile terpenes used in social communication. We have analysed lipids extracted from fur of the tail gland, body (flanks) and muzzle of foxes. GC-MS showed a novel group of iso-valerate and tiglate monoesters of alkane-1,2-diols (C18:0-22:0).

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Background: While most water loss from leaf surfaces occurs via stomata, part of this loss also occurs through the leaf cuticle, even when the stomata are fully closed. This component, termed residual transpiration, dominates during the night and also becomes critical under stress conditions such as drought or salinity. Reducing residual transpiration might therefore be a potentially useful mechanism for improving plant performance when water availability is reduced (e.

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Tea tree oil distilled from Melaleuca alternifolia has widespread use in the cosmetic industry as an antimicrobial as well as for other functions in topical products. Concerns were first raised by the European Commission's Scientific Committee on Consumer Products in 2004 about the level of the potentially carcinogenic phenylpropanoid compound methyl eugenol in tea tree oil. Limits on oil content in different types of cosmetic products were set based on a reported upper level of 0.

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Background And Aims: Drought leading to soil water deficit can have severe impacts on plants. Water deficit may lead to plant water stress and affect growth and chemical traits. Plant secondary metabolite (PSM) responses to water deficit vary between compounds and studies, with inconsistent reports of changes to PSM concentrations even within a single species.

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Plants are dependent on their root systems for survival, and thus are defended from belowground enemies by a range of strategies, including plant secondary metabolites (PSMs). These compounds vary among species, and an understanding of this variation may provide generality in predicting the susceptibility of forest trees to belowground enemies and the quality of their organic matter input to soil. Here, we investigated phylogenetic patterns in the root chemistry of species within the genus Eucalyptus.

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The ether à go-go family of voltage-gated potassium channels is structurally distinct. The N terminus contains an eag domain (eagD) that contains a Per-Arnt-Sim (PAS) domain that is preceded by a conserved sequence of 25-27 amino acids known as the PAS-cap. The C terminus contains a region with homology to cyclic nucleotide binding domains (cNBHD), which is directly linked to the channel pore.

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A number of papers have appeared in recent years proposing the use of enantiomeric ratios of key monoterpenes in Australian tea tree oil (TTO) for detection of adulterated oils. There are however a range of reported values, even from exactly the same suite of authentic oils, and we address here probable reasons for these differences and stress the importance of establishing reference ratios within each laboratory based on oils of known provenance. Any biological variation in the ratio for the key terpene terpinen-4-ol has been demonstrated to be effectively unmeasurable, because the standard deviation on multiple measurements of the same oil is of the same order as that of multiple authentic oils.

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Heme iron has many and varied roles in biology. Most commonly it binds as a prosthetic group to proteins, and it has been widely supposed and amply demonstrated that subtle variations in the protein structure around the heme, including the heme ligands, are used to control the reactivity of the metal ion. However, the role of heme in biology now appears to also include a regulatory responsibility in the cell; this includes regulation of ion channel function.

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